1. Field of the Invention
The present invention relates to a line drawing method for drawing a linear pattern on a non-permeable material, such as resin, by using an inkjet method.
2. Description of the Related Art
In recent years, a method for directly drawing a wiring pattern of an electronic circuit on a substrate by using an inkjet method was proposed. Specifically, a printed circuit board having a desirable circuit pattern thereon can be obtained by directly drawing the desirable circuit pattern on a substrate. The desirable circuit pattern is drawn by ejecting, from an inkjet-type ejection head (inkjet head), droplets of dispersion liquid that contains electrically conductive micro-particles dispersed in a dispersion medium.
Such a drawing method using the inkjet method is used not only in production of printed circuit boards. The drawing method is used also as a means for forming circuits of electrically conductive thin-films in various kinds of devices (for example, a plasma-type display device, a liquid crystal display device, an organic EL (electroluminescence) display device, or the like), thin-films as components of color filters, and the like.
Further, as a method for drawing a linear pattern by using an inkjet method, a method for drawing a linear pattern by uniting droplets of liquid that have landed on a substrate is proposed in Japanese Unexamined Patent Publication No. 2003-266669 (Patent Document 1). In Patent Document 1, the droplets of liquid are united by utilizing a phenomenon that the droplets of liquid, which are wet, spread after they land onto the substrate. Further, a method for drawing a linear pattern by depositing droplets of liquid in an overlapped manner is proposed (please refer to Japanese Patent No. 3578162 (Patent Document 2)). In Patent Document 2, after droplets of liquid are landed onto a substrate, a droplet of liquid is further landed between the droplets of liquid so that they overlap with each other.
However, when a linear pattern is drawn by using an inkjet method, an end of the linear pattern at a drawing start position tends to be thick, compared with other portions of the linear pattern, and that may lower the functional characteristic of the linear pattern.